LEADER FOLLOWING FORMATION CONTROL FOR OMNIDIRECTIONAL MOBILE ROBOTS - The Target Chasing Problem Topics: Autonomous Agents; Control and Supervision Systems; Mobile Robots and Autonomous Systems; Robot Design, Development and Control; Vehicle Control Applications In Proceedings of the 8th International Conference on Informatics in Control, Automation and Robotics - Volume 1: ICINCO, 135-144, 2011 , Noordwijkerhout, Netherlands